Optical systems come in many flavors. Optical communications pulses diodes to transmit information; optical systems such as LIDAR, time-of-flight cameras and range finders, can pulse diodes and measure reflected light to sense the presence, distance information, depth information, and/or speed information of an object. These optical systems can be used in security systems, medical systems, automotive systems, aerospace systems, etc.
Diodes are used often as a light source for many optical applications. Laser diodes are used often due to their ability to generate a great deal of light, though it is not necessary for all applications, and the choice of the light source may naturally depend on the application. Other diodes (e.g., light-emitting diodes) or electrically-driven light sources can be used.
Diodes can emit light as a function the current conducting through the diode. To implement an optical application, a driver is provided to drive the diode, i.e., provide that current to the diode, so that light can be emitted. Diode drivers can vary depending on the requirements of the application, system design, and constraints imposed by the circuit providing the diodes.